The present invention relates to machine recognition of spoken words and more particularly to a method of organizing vocabulary tokens so as to facilitate the finding of tokens which most closely match an unknown spoken word.
As is understood by those skilled in the art, the difficulty with which a spoken word can be recognized increases dramatically as the number of possible words to be recognized increases, i.e., as the vocabulary grows. Whether speech samples are represented by a succession of spectra or by other forms of data encoding, the calculation of the degree of match or vector distance separating two words is computationally intensive. It is therefore important to reduce the number of such computations which must be performed in order to identify an unknown with a reasonable degree of accuracy. This problem is further complicated by the fact that the data points or frames will typically not be distributed at all uniformly over the possible data space.
Among the several objects of the present invention may be noted the provision of a novel speech recognition system; the provision of such a system which provides a high degree of accuracy in word recognition; the provision of such a system which operates quickly; the provision of such a system which is highly reliable; the provision of such a system which is of relatively simple and inexpensive construction. Other objects and features are in part apparent and in part pointed out hereinafter.